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- Author or Editor: V. Markó x
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Neuropteroidea communities were studied near Budapest (Nagykovácsi) in an abandoned, mixed orchard and its neighbouring environment: a shrub community without a closed canopy; a shrub level of the canopied oak forest by using Malaise traps. In the open shrub verge of the orchard larger, and in the oak forest more diverse Neuropteroidea community developed than in the other investigated habitats. The Neuropteroidea communities studied did not show stable compositions in the investigated habitats and years.
The species richness and composition ofAuchenorrhyncha assemblages in three apple orchards in Kent and East Sussex, England was surveyed in 2001 and 2002. Planthoppers, leafhoppers and froghoppers were collected from the tree canopies using yellow sticky traps and a tree beating technique, and from the grass alleyways between the trees using sweep-netting. As a result of intensive sampling, 67 species were collected in an experimental apple orchard at East Malling Research, with a further 30 and 36 species in two organic apple orchards, situated near Marden and Robertsbridge, respectively. A total of 77 species was recorded in the survey. The collection methods applied determined substantially the size and species composition of the samples, the relative abundance of the Auchenorrhyncha species and proportion of males. The most common species collected in the canopy, in decreasing order were: Edwardsiana rosae, Empoasca decipiens, Ribautiana debilis, Edwardsiana crataegi, Empoasca vitis, Philaenus spumarius and Tachycixius pilosus .
About 2500 arthropod species immigrate, or carried by wind, or introduced by man in the orchards, under Hungarian climatic conditions. However, the number of the apple pest species is approximately 30. Owing to the effect of the relationships among the plant-phytophagous-zoophagous species those could colonize the orchard for which the apple provides suitable food sources and whose populations are not regulated or are regulated by a weak efficiency by parasitoids and predators. These populations create the primary pest communities. When the individual number of the parasitoid and predator species is reduced by the broad-spectrum insecticides, the population density of those phytophagous species could increase whose populations was restricted up to that time. In this case the secondary pest communities could develop. The integrated pest management provides the possibilities to solve the problems caused by the regular use of broad-spectrum insecticides. The real requirement is to find and to harmonize those methods which regulate the population dynamics of the species of the primary pest communities.
Epidemiological, pathological, serological and virological investigations are reported on turkey haemorrhagic enteritis virus (THEV) infection in Hungarian turkey flocks. The pathogenesis of infection in experimentally infected turkeys and chickens, as well as the usefulness of polymerase chain reaction (PCR)/sequencing method for epidemiological investigation and for the differentiation of vaccine and field strains of THEV was also studied. Since the first recognition of the disease in Hungary in the late 1970s, until recently the disease has been diagnosed sporadically in its mild form. In the last few years (2000–2005), however, the number of outbreaks and the severity of the disease increased (9–23 affected flocks/year). Most of the outbreaks occurred at the age of 6 to 8 weeks and was complicated with Escherichia coli infection. The antibody levels to THEV in turkey flocks gradually declined till 5–7 weeks of age, and then they increased sharply due to natural infection with THEV. The immune response to vaccination (at 5 weeks of age) showed no significant antibody level increase one week postvaccination, but four weeks later the antibody level reached high values and then remained at this high level. The agar gel immunodiffusion (AGID) test to detect turkey adenovirus A (TAdV-A) antigen and PCR methods for THEV-specific DNA gave similarly positive results if spleens with pathognomonic lesions were tested; however, PCR proved to be more sensitive in cases with less characteristic pathological lesions. Nucleotide sequence alignment of PCR products amplified from Hungarian field strains and the Domermuth vaccine strain and that of the published THEV hexon sequences in GenBank database revealed slight differences between the sequences.
